🍪 The GLP Lounge uses cookies to improve your experience, analyze traffic, and personalize content. By continuing to use this site, you agree to our Cookie Policy.
Evidence-based GLP-1 & peptide discussion since 2023
ForumsCompounding & FormulationEndotoxin testing in compounded injectables — 6 month update

Endotoxin testing in compounded injectables — 6 month update

CarlaRPh_TPA Thu, Mar 19, 2026 at 8:58 AM 9 replies 681 viewsPage 1 of 2
CarlaRPh_TPA
Senior Member
1,890
8,234
Jan 2024
Tampa, FL
Mar 19, 2026 at 8:58 AM#1

Two pharmacies quoted me last year, one describing itself as 503A and one as 503B, and I assumed 503B just meant bigger until both stopped within weeks of each other.

Two things anyone can check: a state licence number for a 503A, and an FDA outsourcing-facility registration for a 503B. Both are publicly searchable, and a pharmacy unwilling to give you either has answered the question.

What I actually want to know is why a shortage listing created a legal pathway at all, since a shortage is a supply fact rather than a permission.

Tell me what I have not thought of.

8 3FDA_TrackerJim, ricardo_MIA, BrianDallas92 and 5 others
Reply Quote Save Share Report
PeptideChemSF
Senior Member
1,890
9,012
Jan 2024
San Francisco, CA
Mar 19, 2026 at 9:16 AM#2

This one has a reasonably settled answer, so here it is. The shortage clause is the answer to the second question and it is a subtraction rather than an addition. Both exemptions forbid compounding something that is essentially a copy of a commercially available approved product. A product FDA has listed as in shortage is not treated as commercially available, so listing removed the objection that otherwise blocked compounding. It never created a permission; it withdrew a prohibition, which is why it evaporated the moment the supply fact changed.

7 2dave_SLC, FDA_TrackerJim, ricardo_MIA and 4 others
Reply Quote Save Share Report
KristenIndy
Member
623
2,678
May 2024
Indianapolis, IN
Mar 19, 2026 at 9:34 AM#3
PeptideChemSF said:
The shortage clause is the answer to the second question and it is a subtraction rather than an addition.

Agreed, and the enforcement dates were staggered by category — 503A first, 503B a few weeks later — because outsourcing facilities have manufactured inventory and clinic contracts to unwind while a 503A makes to order.

Last edited: Mar 19, 2026 at 2:34 PM
6 1Dr.GutHealth, amsterdam_pete, LondonLisa and 3 others
Reply Quote Save Share Report

Sigma-Aldrich — Research-Grade Standards

Certified reference materials, analytical reagents, and research-grade standards for peptide verification. Trusted by laboratories worldwide.

Shop Reference Standards
BiostatsBrad
Member
456
2,345
Jul 2024
Durham, NC
Mar 19, 2026 at 9:52 AM#4
CarlaRPh_TPA said:
Two pharmacies quoted me last year, one describing itself as 503A and one as 503B, and I assumed 503B just meant bigger until both stopped within…

Same position here, arrived at the long way round. They are two different exemptions from the same federal requirements and they buy different things. A 503A pharmacy is regulated primarily by the state board, needs a patient-specific prescription, is exempt from CGMP, and may use a bulk substance that has a USP monograph, is a component of an approved drug, or appears on the 503A bulks list — three independent doorways. A 503B outsourcing facility registers with the FDA, is inspected on a risk basis, must comply with CGMP, may compound for office stock without a patient-specific prescription, and has one doorway to a permitted bulk substance: the 503B bulks list, or the drug shortage list.

5 0james_edin, FranDenver, Dr.BariatricHTX and 2 others
Reply Quote Save Share Report
SleepDoc_PDX
Member
289
1,234
Sep 2024
Portland, OR
Mar 19, 2026 at 11:28 AM#5

From the other side of the consultation, briefly.

GMP compliance checklist relevant to compounded supply compounding quality:

  • Clean room environment with HEPA filtration
  • Environmental monitoring (viable and non-viable)
  • Personnel training and competency assessment
  • Validated analytical methods for testing
  • Stability testing program
  • Complete batch records and traceability
  • Quality management system with deviation handling

A 503B pharmacy following cGMP should be able to answer questions about ALL of these if you ask. Don't be afraid to ask — it's your health.

4 24mel_PDX, Dr.AddMedPHL, newstart_MO and 1 other
Reply Quote Save Share Report

Similar Threads

503A vs 503B compounding — regulatory framework explained4 replies
Compounded semaglutide stability: accelerated degradation study results6 replies
Lyophilized vs liquid peptides — stability and bioavailability comparison18 replies
Bacteriostatic water sourcing and sterility considerations8 replies
State-by-state compounding pharmacy regulations — 2026 map8 replies
ForumsNewTrendingMembersAccount

Log In

Forgot password?
No account? Register